review request (M): 7121140: Allocation paths require explicit memory synchronization operations for RMO systems

Tom Rodriguez tom.rodriguez at
Wed Dec 14 13:01:47 PST 2011

On Dec 14, 2011, at 12:35 PM, Roland Westrelin wrote:

>> I think the instruct name should be membar_storestoree instead of unnecessary_membar_storestore and remove the "unnecessary so" part of the comment.  It's like membar_release where it's necessary but it never emits any assembly.
> Makes sense. I'll change that before I push it.
>> I wouldn't expect this to affect performance since it's not emitting an extra instructions but we are emitting some extra barriers which tangles of the memory graph a bit.  Could you do some quick performance to make sure nothing's changed?
> Ok. I'll do that. Would specjvm98 + specjbb2005 on x86 be sufficient?



>> Otherwise it looks good.
> Thanks for the review.
> Roland.

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